1. Field of the Invention
The present invention relates to ball bats. More precisely, the present invention relates to a ball bat having means to conserve the kinetic energy from a ball impact for a lively rebound, and to dampen the sound and vibration created by the impact.
2. Description of Related Art
A ball bat is most commonly found in the game of baseball, which dates back to the early 1800s. Baseball bats are usually made from a solid plank of lumber that is turned on a lathe to obtain the familiar baseball bat shape. The bat is sanded down to a smooth exterior finish and then sealed with varnish or similar type covering.
The game of baseball grew to be a national past-time. Meanwhile, the game also inspired variations of the sport, the most popular of which is softball. Little league ball, slow pitch softball, as well as T-ball became popular for younger players. The common thread throughout these sporting games is the ball and bat.
The bats used in these games varied widely in size, shape, weight, and construction. Furthermore, innovative individuals continually improved the performance of bats to give the player an edge over the competition.
For example, after the original wooden bat came the metal bat. Typically, the metal bat was made from an aluminum alloy and was hollow inside. The bats were made from a tube of aluminum, wherein a swaging machine formed the tube into a bat profile. The were three major sections of the bat: namely, the barrel portion, the tapered portion, and the handle portion. A cap covered the opening at the top end of the tube while a knob covered the bottom opening of the tube. The swaging operation was necessary to decrease the diameter of the handle portion to a dimension smaller than the diameter of the barrel portion to allow players to easily grip the bat.
Aside from aluminum alloys, magnesium, titanium, and even ceramics have been used to make bats. There are even composite bats made of carbon fiber embedded in silicon glass and laminated to form a precise shell.
For anyone who has swung a bat and hit a ball, he or she is very cognizant of the noise and vibration perceived at the instant of impact between the bat and ball. The shock to the senses is violent and jarring. To be sure, we are all familiar with the crack of the baseball bat when a homer is struck in the ball park.
Bat makers of hollow, metallic bats added a spongy material to the hollow interior as a means to dampen vibration and noise. Other manufacturers filled the interior of the hollow bats with foam material for the same purpose. But the foam or spongy material had low resilience so when deformed, there was minor spring back or slow recovery for the material to re-assume its initial shape. Hence, the conventional method of using sponges or foam damped vibrations or sound to some extent, but the rebound performance of the bat did not improve. Thus, the overall performance and playability of the bat did not greatly improve.
Another attempt at damping the vibration and sound of the bat during impact was through adding a highly viscous liquid such as oil and shotgun shot into the hollow bat. The metal shot and oil were encased in an area below the tapered part of the bat at the handle portion. This modification had practical problems including oil leaks.